This invention relates generally to a system and method for inserting individualized data content into a compressed digital data stream and in particular to a system and method for inserting individualized data content into a compressed digital video and audio data stream being transmitted to a plurality of viewers by any type of broadcast system, such as a satellite-based, cable-based, wireless cable (i.e., microwave) or terrestrial broadcast system.
Prior to the introduction of cable television and the like, a television receiver received its television signals from the antenna connected to the television. However, for someone in a remote location or where television signals are blocked, such as a high rise apartment, the reception of the antenna was so poor that the person was unable to watch television at all. To solve such problems, television signals may be transmitted over cables or satellite-based systems that permit the user to view any television program available on the cable or satellite without an antenna. The cable system typically transmits local television stations to the user while a satellite system transmits the same television signals to all of its user across the entire country so that a television viewer in California may watch a New York television station. These conventional cable and satellite systems generate and transmit analog television signals that are received by a set-top box in the home of the television viewer and then displayed on the television screen. With these systems, the operator of the local cable system may easily insert local advertisements and data content into the analog data stream. The local advertisements and data content, however, that are added into the data stream are the same for every subscriber to that cable system.
In addition, with conventional television transmissions systems, television broadcasters are limited by the channel capacity between their last stage transmission facility (e.g., satellite, cable head-end or broadcast station) and their viewers. Thus, on any given channel, viewers served by that transmission facility receive the same programming data at the same time. From an advertising perspective, this means that every viewer watching that channel views the same commercials. This prevents satellite operators, for example, from being able to offer localized advertising because their satellite broadcasts to the entire country at once. Cable operators, however, are able to offer localized commercials within their subscriber area since their head-end facilities are geographically distributed. Neither the satellite operator nor the cable operator, however, can provide targeted commercials that are directed to a particular user or provide the ability to factor viewer preferences into determining what local content is being shown to a viewer.
It is desirable to deliver television programming to consumers in a more targeted manner than is possible with existing cable or satellite systems. In particular, it is desirable to be able to, for example, deliver geographically localized content to a particular area over a non-geographically localized transmission medium, such as a satellite system. Some conventional systems use the Internet or data casting to deliver individualized content to a viewer, but these systems do not permit a satellite system to transmit localized content or permit the operator of the satellite system to control the local content.
Some conventional cable and satellite-based television systems and most future systems are going to be transmitting their television signals in a digital compressed data format in order to make more efficient use of the bandwidth of the cable or the satellite system. The data is typically compressed using the Motion Pictures Experts Group (MPEG) format due to the high compression rates which reduce the bandwidth required to transmit the data. Although this compressed digital data stream is more compact, it is more difficult to insert local content within these compressed digital data streams. By contrast, a conventional still image compression scheme, such as Joint Photographic Experts Group (JPEG), may have data more easily inserted within the data stream since there is not any motion compensation required. These still image compression schemes, however, do not provide sufficient compression for video data streams. Thus, a motion compensation based compression scheme, such as MPEG, is used which involves using predictive methods to reduce the temporal redundancies (i.e., portions of the screen that may have the same image for a predetermined period of time) inherent in typical video data streams. Thus, MPEG has a higher level of compression due to these predictive methods, but also creates temporal dependencies (i.e., a frame of the data stream requires data from some other frame in order to actually recreate the image in the frame) in the compressed data. Thus, in order to insert data within a compressed data stream, these temporal dependencies must be recognized and some technique for solving the problems associated with these temporal dependencies is needed.
Thus, it is more difficult to insert data into a compressed digital data stream. In addition, as described above, there is no conventional system which permits local targeted content, that is inserted into a compressed digital data stream or an analog data stream, to be customized for a particular user of the system. As described above, one conventional cable system permits an operator of the system to insert local content into an analog data stream, but that local content is the same for all of the users that subscribe to that operator's system. Therefore, it is desirable to provide a compressed digital data stream of video into which local content may be inserted and to provide a system that may customize the local content displayed on each user's television based on some predetermined preferences of the user.
Thus, there is a need for a system and method for providing individualized local content in digital or analog data streams which avoid these and other problems of known systems and methods, and it is to this end that the present invention is directed.